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#ifndef _ncvThresholdOp_H_
#define _ncvThresholdOp_H_

#include "ncvImage.h"

/**
 * \class CThresholdOp
 * \brief Provides CNokiaCVImage with a threshold operation.
 * Creates an black&white bitmap from CNokiaCVImage by thresholding.
 * Implements two thresholding methods:
 *	- simple with static threshold value
 *  - adaptive
 * \note Symbian TClass.
 *
 */
class CThresholdOp : public CImageOp
	{
public:
	IMPORT_C enum TThresholdType
		{
		EMean,
		EMinMax
		};
	/**
	 * \brief Constructor for thresholding with given value.
	 * \param aImage CNokiaCVImage to apply the thresholding to.
	 * \param aThresholdValue an integer value (0-255) to use as a threshold.
	 */
	IMPORT_C CThresholdOp( CNokiaCVImage* aImage, TUint8 aThresholdValue);

	/**
	 * \brief Constructor for adaptive thresholding.
	 * \param aImage CNokiaCVImage to apply the thresholding to.
	 * \param aSize	aSize x aSize neighborhood to use for adaptation
	 * \param aConstant Constant value that is subtracted from the mean.
	 */
	IMPORT_C CThresholdOp( CNokiaCVImage* aImage, TInt aSize, TInt aConstant, TThresholdType = EMean);

	/**
	 * \brief Do the operation.
	 * \param aTarget CNokiaCVImage to store the result in.
	 * \note the function can leave
	 */
	IMPORT_C void DoOperation( CNokiaCVImage* aTarget );

private:
	void DoValueThresholdL(CNokiaCVImage* aTarget);
	void DoAdaptiveThresholdL(CNokiaCVImage* aTarget, TInt aSize, TInt aConstant);
	TUint32 GetMeanThresholdL(CPixelAccess* pa, TPoint aPoint, TSize aSizeOfImage, TInt aSize, TInt aConstant);
	TUint32 GetMinMaxMeanThresholdL(CPixelAccess* pa, TPoint aPoint, TSize aSizeOfImage, TInt aSize, TInt aConstant);

	CNokiaCVImage*	iImage;
	TUint8		iThreshold;
	TBool		iAdaptive;
	TInt		iSize;
	TInt		iConstant;
	TThresholdType 	iType;
	};

#endif
